Dental scaling is effective for some bad breath such as that caused by calculus, but not for bad breath caused by gastrointestinal diseases. If there are more calculus on the teeth, or with gingivitis symptoms, it is easy to have bad breath. Dental scaling can wash away calculus, plaque and other factors that cause bad breath, at this time scaling is useful. You should pay attention to oral hygiene and brush your teeth. In addition, some bad breath is not due to oral causes, such as gastrointestinal diseases such as Helicobacter pylori infection is prone to oral odor phenomenon, you can use the appropriate medication to alleviate the phenomenon of bad breath. If the phenomenon of bad breath is obvious, you should go to the hospital in time for examination and appropriate treatment.